Astronomy Picture Of the Day (APOD)Composing the Omega Nebula
The Omega Nebula is a massive, complex cloud of dust and gas from which new stars are continually forming. The similarity to the Greek letter capital Omega gives the molecular cloud its popular name, but the nebula is also known as the Swan Nebula, the Horseshoe Nebula, and M17.
Too Close to a Black Hole
What would you see if you went right up to a black hole? Above are two computer generated images highlighting how strange things would look. On the left is a normal star field containing the constellation Orion. Notice the three stars of nearly equal brightness that make up Orion's Belt.
Apollo 17 Lunarscape: A Magnificent Desolation
Buzz Aldrin, Apollo 11 Lunar Module pilot and the second human to walk on the Moon, described the lunar landscape as "a magnificent desolation". Dramatic pictures from the Apollo missions to the lunar surface testify to this apt turn of phrase.
Abell 1795: A Galaxy Cluster s Cooling Flow
Throughout the Universe, galaxies tend to swarm in groups ranging from just a handful of members to casts of thousands. Astronomers have realized since the early 1970s that the larger swarms, immense clusters of galaxies millions of light-years across, are immersed within tenuous clouds of hot gas which glow strongly in x-rays.
Earths San Andreas Fault
The Earth's surface is broken. Cracks in the Earth's crust known as faults can run for hundreds of kilometers. These faults are frequently the sites of major earthquakes as the tectonic plates that cover the surface of the Earth shift.
In the famous Pleiades star cluster, a star's light is slowly destroying a passing cloud of gas and dust. The star, Merope, lies just off the upper right edge of this recently released picture by the Hubble Space Telescope.
Layered Mars: An Ancient Water World
Pictured above, layers upon layers stretch across the floor of West Candor Chasma within the immense martian Valles Marineris. Covering an area 1.5 by 2.9 kilometers, the full image from the Mars Global Surveyor spacecraft shows over 100 individual beds.
The Circinus Galaxy
Powerful forces are at play in the nearby Circinus Galaxy. Hot gas, colored pink, is being ejected out of the spiral galaxy from the central region. Much of Circinus' tumultuous gas, however, is concentrated in two rings.
Earth's North Magnetic Pole
A magnetic compass does not point toward the true North Pole of the Earth. Rather, it more closely points toward the North Magnetic Pole of the Earth. The North Magnetic Pole is currently located in northern Canada.
SN 1006: Pieces of the Cosmic Ray Puzzle
Research balloon flights conducted in 1912 by Austrian physicist Victor Hess revealed that the Earth was constantly bombarded by high energy radiation from space - which came to be called "Cosmic Rays". What are Cosmic Rays and where do they come from?